From 4206b53c09ce049c68b6c8decdc220f6687468b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian@centricular.com>
Date: Wed, 8 Apr 2020 15:24:07 +0300
Subject: [PATCH] Mark GMutex mutex guards as #[must_use]

See gstreamer-rs commit b21f5764309f9f65666016a9069e1b938935e6f2
---
 generic/threadshare/src/lib.rs                  | 1 +
 utils/fallbackswitch/src/base/aggregator_pad.rs | 2 +-
 utils/fallbackswitch/src/base/utils.rs          | 1 +
 3 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/generic/threadshare/src/lib.rs b/generic/threadshare/src/lib.rs
index 42ecc114..beb53569 100644
--- a/generic/threadshare/src/lib.rs
+++ b/generic/threadshare/src/lib.rs
@@ -85,6 +85,7 @@ pub fn set_element_flags<T: glib::IsA<gst::Object> + glib::IsA<gst::Element>>(
     }
 }
 
+#[must_use = "if unused the Mutex will immediately unlock"]
 struct MutexGuard<'a>(&'a glib_ffi::GMutex);
 
 impl<'a> MutexGuard<'a> {
diff --git a/utils/fallbackswitch/src/base/aggregator_pad.rs b/utils/fallbackswitch/src/base/aggregator_pad.rs
index eb57f614..38c47327 100644
--- a/utils/fallbackswitch/src/base/aggregator_pad.rs
+++ b/utils/fallbackswitch/src/base/aggregator_pad.rs
@@ -21,7 +21,7 @@ impl<O: IsA<AggregatorPad>> AggregatorPadExtManual for O {
     fn get_segment(&self) -> gst::Segment {
         unsafe {
             let ptr: &gst_base_sys::GstAggregatorPad = &*(self.as_ptr() as *const _);
-            super::utils::MutexGuard::lock(&ptr.parent.object.lock);
+            let _guard = super::utils::MutexGuard::lock(&ptr.parent.object.lock);
             from_glib_none(&ptr.segment as *const gst_sys::GstSegment)
         }
     }
diff --git a/utils/fallbackswitch/src/base/utils.rs b/utils/fallbackswitch/src/base/utils.rs
index dca8cf69..ff456cd0 100644
--- a/utils/fallbackswitch/src/base/utils.rs
+++ b/utils/fallbackswitch/src/base/utils.rs
@@ -9,6 +9,7 @@
 use glib::translate::mut_override;
 use glib_sys;
 
+#[must_use = "if unused the Mutex will immediately unlock"]
 pub struct MutexGuard<'a>(&'a glib_sys::GMutex);
 
 impl<'a> MutexGuard<'a> {